Insight rifampicin-resistant (rpoB) mutation in Pseudomonas stutzeri leads to enhance the biosynthesis of secondary metabolites to survive against harsh environments.

In this study, a wild-type and five distinct rifampicin-resistant (Rif r ) rpoB mutants of Pseudomonas stutzeri (i.e., Q518R, D521Y, D521V, H531R and I614T) ability were investigated against harsh environments (particularly nutritional complexity). Among these, the robust Rif r phenotype of P. Stutzeri was associated only with base replacements of the amino deposits. The use of carboxylic and amino acids significantly increased in various Rif r mutants than that of wild type of P. stutzeri. The assimilation of carbon and nitrogen (N) sources of Rif r mutants' confirmed that the organism maintains the adaptation in nutritionally complex environments. Acetylene reduction assay at different times also found the variability for N-fixation in all strains. Among them, the highest nitrogenase activity was determined in mutant 'D521V'. The assimilation of carbon and nitrogen sources of P. stutzeri and its Rif r mutants ensures that the organism maintains the adaptability in nutritionally complex environments through fixing more nitrogen.